Recently, the Shanghai Institute of Applied Physics, Chinese Academy of Sciences and Monash University, IBM, etc., through the DNA-induced gold nanoparticles self-assembly prepared two-dimensional single-layer gold nano-film, can achieve the humidity response of the color change. Journal of Materials.
The excellent photophysical properties of two-dimensional nanomaterials show an important application prospect in nanometer light / electricity, biosensing analysis and so on.However, how to construct two-dimensional nanomaterials from bottom-up by self-assembly method With the macro optical properties of the device is a difficult.Shanghai Institute of Physical Biology, Dr. Shen Shenlei, etc. under the guidance of researcher Fan Chunhai, and through the IBM company professor Zhou Ruhong and Australia Monash University professor Cheng Wenlong cooperation, through DNA specificity It is interesting to note that the color of the monolayer gold nanofilm is reversibly changed with the change of the surrounding water content.The theoretical calculation shows that under the wet state, the gold nanoparticles can be transformed into a single layer of gold nanoparticles at different interfaces. DNA is stretched, and the distance between the nanoparticles is far away.When the DNA is crimped in the dry state, the distance between the particles is reduced.The change of the particle spacing will change the degree of coupling of the surface plasmon resonance of the gold nanoparticles.Through the study of the sample Of the surface-enhanced Raman spectroscopy, the researchers found that in the dry state of the nanoparticles between the localized particles Significantly enhanced. This result reveals the mechanism on a macroscopic scale due to the surface plasmon coupling synergistic color change.
This phenomenon has potential application value in humidity monitoring, biosensing, information storage and photovoltaic.
